<template>
  <div id="home">
    <nav-bar class="home-nav">
      <div slot="center">购物车</div>
    </nav-bar>
    <tab-control
      :titles="['流行', '新款', '精选']"
      @tabClick="tabClick"
      ref="tabControl1"
      class="tabControl"
      v-show="isTabFixed"
    ></tab-control>
    <scroll :probe-type="3" :pull-up-load="true" class="content" ref="scroll" @scroll="contentScroll" @pullingUp="loadMore">
      <home-swiper :banners="banners" @swiperImageLoad="swiperImageLoad"></home-swiper>
      <recommend-view :recommends="recommends"></recommend-view>
      <feature-view></feature-view>
      <tab-control :titles="['流行', '新款', '精选']" @tabClick="tabClick" ref="tabControl2"></tab-control>
      <goods-list :goods="showGoods"></goods-list>
    </scroll>
    <back-top @click.native="backClick" v-show="isShowBackTop"></back-top>
  </div>
</template>

<script>
import NavBar from 'components/common/navbar/NavBar.vue'
import Scroll from 'components/common/scroll/Scroll.vue'

import TabControl from 'components/content/tabControl/TabControl.vue'
import GoodsList from 'components/content/goods/GoodsList.vue'
import BackTop from 'components/content/backTop/BackTop.vue'

import HomeSwiper from './component/HomeSwiper.vue'
import RecommendView from './component/RecommendView.vue'
import FeatureView from './component/FeatureView.vue'

import { getHomeMultiData, getHomeGoods } from 'network/home'

import { debounce } from 'common/utils'

import { itemListenerMixin } from '../../common/mixin'

export default {
  name: 'Home',
  mixins: { itemListenerMixin },
  components: {
    NavBar,
    Scroll,
    TabControl,
    GoodsList,
    BackTop,
    HomeSwiper,
    RecommendView,
    FeatureView,
    BackTop
  },
  data() {
    return {
      banners: [],
      recommends: [],
      goods: {
        pop: { page: 0, list: [] },
        new: { page: 0, list: [] },
        sell: { page: 0, list: [] }
      },
      currentType: 'pop',
      isShowBackTop: false,
      tabOffsetTop: 0,
      isTabFixed: false,
      saveY: 0
    }
  },
  computed: {
    showGoods() {
      return this.goods[this.currentType].list
    }
  },
  created() {
    // 1.请求多个数据
    this.getHomeMultiData()
    // 2.请求商品数据
    this.getHomeGoods('pop')
    this.getHomeGoods('new')
    this.getHomeGoods('sell')
  },
  mounted() {
    // 1.图片加载完成的事件监听
    const refresh = debounce(this.$refs.scroll.refresh, 50)
    this.$bus.$off('itemImageLoad').$on('itemImageLoad', () => {
      refresh()
    })
  },
  activated() {
    this.$refs.scroll.scrollTo(0, this.saveY, 0)
    this.$refs.scroll.refresh()
  },
  deactivated() {
    this.saveY = this.$refs.scroll.getScrollY()
  },
  methods: {
    /**
     * 事件监听相关的方法
     */
    tabClick(index) {
      switch (index) {
        case 0:
          this.currentType = 'pop'
          break
        case 1:
          this.currentType = 'new'
          break
        case 2:
          this.currentType = 'sell'
          break
      }
      this.$refs.tabControl1.currentIndex = index
      this.$refs.tabControl2.currentIndex = index
    },
    backClick() {
      this.$refs.scroll.scrollTo(0, 0)
    },
    contentScroll(position) {
      // 1.判断BackTop是否显示
      this.isShowBackTop = -position.y > 1000 ? true : false
      // 2.决定tabControl是否吸顶（pisition：fixed）
      this.isTabFixed = -position.y > this.tabOffsetTop
    },
    loadMore() {
      this.getHomeGoods(this.currentType)
      this.$refs.scrollrefresh()
    },
    /**
     * 网络请求相关的方法
     */
    getHomeMultiData() {
      getHomeMultiData().then(res => {
        this.banners = res.data.banner.list
        this.recommends = res.data.recommend.list
        console.log('轮播图列表:', this.banners)
        console.log('推荐列表:', this.recommends)
      })
    },

    getHomeGoods(type) {
      const page = this.goods[type].page + 1
      getHomeGoods(type, page).then(res => {
        this.goods[type].list.push(...res.data.list)
        this.goods[type].page += 1
        this.$refs.scroll.finishPullUp()
        console.log('首页商品数据::', this.goods)
      })
    },

    swiperImageLoad() {
      this.tabOffsetTop = this.$refs.tabControl2.$el.offsetTop
      // console.log(this.$refs.tabControl.$el.offsetTop)
    }
  }
}
</script>

<style scoped>
#home {
  position: relative;
  /* padding-top: 44px; */
  height: 100vh;
}
.home-nav {
  background-color: var(--color-tint);
  color: #fff;
  /* 在使用浏览器原生滚动时，为了让导航不跟随一起滚动 */
  /* position: fixed;
  left: 0;
  right: 0;
  top: 0;
  z-index: 9; */
}
/* .tab-control {
  position: sticky;
  top: 44px; 
}  */
.content {
  position: absolute;
  top: 44px;
  bottom: 49px;
  left: 0;
  right: 0;
  overflow: hidden;
}
.tab-control {
  position: relative;
  z-index: 9;
}
/* .content {
  height: calc(100% - 44px -49px);
  overflow: hidden;
} */
</style>
